I have some real coal dust and was wondering if it’s a good idea to use it on my layout. I plan to securely glue it in place. Anyone know of a reason to not do this?
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I would say go ahead, but you may want to trial your fixing method to see if it looks as good as you hope it will, but also to see if the fixative leaches out some nasty and weird stuff from the coal. Coal has some volatiles and stuff that may not play nice with your modelling, even if it only leaves an unsightly colour like a tan, orange or reddish stain. Certainly keep it out of your engine works and any rods, power wipers, turnout throwbars and points areas, etc.
Are you intending to use it in scenicking or in hoppers (just read the post below and he raises a good point).
-Crandell
Are you sure you want to have it permanently glued to your hopper cars? Maybe if you line the inside with celophane first, then you can pour in the coal dust, pour on the glue, peel off the celophane after the glue dries and - wa-lah - a removable, solid coal load. Then you can do empties-in/loads-out operations.
I was talking to a geologist about a similar project and he gave me advice that turned me away from my original idea. Coal will oxidize over time. What happens is that it will fall apart and turn into an ashy substance.
Just a thought.
As any metallurgist will tell you, there’s no such thing as, “Just plain coal.”
There are low-grade lignites that will powder at a harsh glance. OTOH, sculptors have carved anthracite into artistic shapes that have lasted for decades without degradation. In between, there are about as many sub-classes of coal as there are mines which produce it, with a bewildering array of contaminants and qualities.
Then, too, coal which maintains its integrity in full-scale baseball-size lumps may deteriorate in a hurry when those lumps are reduced to 1:80 scale size product. If that deterioration happens in the populated portion of your humble abode…
Hence my decision to model a rather friable grade of sub-Bituminous with pool-filter charcoal. And to keep all phases of the operation out of the inhabited spaces of my dwelling.
Chuck (Modeling Central Japan in September, 1964 - with collieries.)
I have a very large wooden crate behind my shop full of coal. I smash it between two metal plates and brake it into Ho scale usable pieces. This is no revelation or discovery I can take credit for on my part.
This is exactly the same method used by Smith &sons Ballast, Arizona Rock & Mineral and several very well known model railroaders. There’s nothing wrong with using the real thing when it comes to model railroading with the exception of using real water.thats a basic no no.
many modelers sift real dirt to use as ground cover some sue real sand where applicable etc. the basic rule of thumb is besides sifting the heck out of it to give you the grade you want, you run a good strong magnet through it to see if you have a high iron content or not. High iron = conductivity which means shorts circuits galore, the second thing you do is spread it out on a dollar store cookie sheet and bake it in your oven (when your wife is not around) @ about 400 degrees for approx. 45 min. or until fully dry. This is supposed to kill any microbes etc. living in the soil. I don’t believe you would need to do this with coal but I can’t say for sure.
I have plenty of real coal dust and lumps of coal used as ground cover in my coal mining area and all around the tipple etc. show me a real coal mine with nice green grass. Same goes for my engine servicing facility. I used a base of black sand and Arizona Rock & Mineral Southern Pacific fine ballast for track ballast and ground cover in the yard. Again show me nice green grass ans shrubbery in or around a steam era engine facility, you ain’t cause nothing grows with maybe the exception of the ocassioanl weed in a place like that.
As far as securing it to your layout the usual methods work fine straight white glue for ground cover area;s and the alcohol and 50/50 white glue & water ballasting method works just fine.
Back in the '60s MR did a two page photo spread on the GATSME lines layout in the Philadelphia area. One of the club members there had acquired some iron ore from Northern Minnesota which he had loaded into a string of ore cars which he lugged around behind a duet of Akane(?) M3/M4 Yellowstones. The narrative accompanying the photograph did not say whether the ore was permanently afixed in the cars.
I guess if this guy did it with iron ore you can do it with coal.
Well, in time of dire needs, you could burn the layout coal combination for fire wood. 
Rather than filling the hopper with coal and gluing, cut a piece of styrofoam insulation to fit inside and carve a coal load like contour on the top. Paint with black latex or acrylic paint then sprinkle the wet paint with the coal. If necessary, do a final fix with dilute white glue or similar adhesive. It will make your material go a lot farther.
Why do you brake it? Is it going too fast? [:D]